Alcohol may increase risk for certain types of breast cancer

Alcohol is a known risk factor for breast cancer, but it may not be equally risky for all subtypes of the disease. In particular, according a new study released today by the Journal of the National Cancer Institute, alcohol appears more important for “hormone-sensitive” breast cancers — with drinkers showing more pronounced risk of invasive lobular carcinoma and of hormone-receptor-positive tumors.

That new research comes from data on more than 2,000 women who participated in the Women’s Health Initiative study in the mid-1990s, and who were diagnosed with breast cancer during that period. Compared to women who never drank, women who consumed more than seven drinks per week at the beginning of the study period, in 1993, had an almost twofold increase in the risk of developing hormone-receptor-positive invasive lobular carcinoma. But there was no significant difference between the drinkers and the non-drinkers in their rates of developing invasive ductal carcinoma, a somewhat more common form of breast cancer.

The researchers say their results hint at unique disease-formation processes for the subtypes of breast cancer.